Backing up what @H2CO3 said, the libs team explicitly reserves the right to change Debug output but as far as I know we make no such guarantees about Display, so my understanding is that we currently treat Display output as part of our stable API. That said, we already have a history of making small breaking changes to our API when we think the breakage is minor enough / justified, such as adding an Error impl for &E: Error, so I imagine we would likewise make special exceptions to Display format in some cases. The wording in error messages in particular springs to mind, where we may want to update one to clarify its meaning.
3 Likes